//
// Copyright (c) 2009-2010 Mikko Mononen memon@inside.org
//
// This software is provided 'as-is', without any express or implied
// warranty.  In no event will the authors be held liable for any damages
// arising from the use of this software.
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it
// freely, subject to the following restrictions:
// 1. The origin of this software must not be misrepresented; you must not
//    claim that you wrote the original software. If you use this software
//    in a product, an acknowledgment in the product documentation would be
//    appreciated but is not required.
// 2. Altered source versions must be plainly marked as such, and must not be
//    misrepresented as being the original software.
// 3. This notice may not be removed or altered from any source distribution.
//

#define _USE_MATH_DEFINES
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "SDL.h"
#include "SDL_opengl.h"
#include "imgui.h"
#include "NavMeshTesterTool.h"
#include "Sample.h"
#include "Recast.h"
#include "RecastDebugDraw.h"
#include "DetourNavMesh.h"
#include "DetourNavMeshBuilder.h"
#include "DetourDebugDraw.h"
#include "DetourCommon.h"

#ifdef WIN32
#    define snprintf _snprintf
#endif

// Uncomment this to dump all the requests in stdout.
#define DUMP_REQS

// Returns a random number [0..1)
static float frand()
{
//    return ((float)(rand() & 0xffff)/(float)0xffff);
    return (float)rand()/(float)RAND_MAX;
}

inline bool inRange(const float* v1, const float* v2, const float r, const float h)
{
    const float dx = v2[0] - v1[0];
    const float dy = v2[1] - v1[1];
    const float dz = v2[2] - v1[2];
    return (dx*dx + dz*dz) < r*r && fabsf(dy) < h;
}


static int fixupCorridor(dtPolyRef* path, const int npath, const int maxPath,
                         const dtPolyRef* visited, const int nvisited)
{
    int furthestPath = -1;
    int furthestVisited = -1;
    
    // Find furthest common polygon.
    for (int i = npath-1; i >= 0; --i)
    {
        bool found = false;
        for (int j = nvisited-1; j >= 0; --j)
        {
            if (path[i] == visited[j])
            {
                furthestPath = i;
                furthestVisited = j;
                found = true;
            }
        }
        if (found)
            break;
    }

    // If no intersection found just return current path. 
    if (furthestPath == -1 || furthestVisited == -1)
        return npath;
    
    // Concatenate paths.    

    // Adjust beginning of the buffer to include the visited.
    const int req = nvisited - furthestVisited;
    const int orig = rcMin(furthestPath+1, npath);
    int size = rcMax(0, npath-orig);
    if (req+size > maxPath)
        size = maxPath-req;
    if (size)
        memmove(path+req, path+orig, size*sizeof(dtPolyRef));
    
    // Store visited
    for (int i = 0; i < req; ++i)
        path[i] = visited[(nvisited-1)-i];                
    
    return req+size;
}

// This function checks if the path has a small U-turn, that is,
// a polygon further in the path is adjacent to the first polygon
// in the path. If that happens, a shortcut is taken.
// This can happen if the target (T) location is at tile boundary,
// and we're (S) approaching it parallel to the tile edge.
// The choice at the vertex can be arbitrary, 
//  +---+---+
//  |:::|:::|
//  +-S-+-T-+
//  |:::|   | <-- the step can end up in here, resulting U-turn path.
//  +---+---+
static int fixupShortcuts(dtPolyRef* path, int npath, dtNavMeshQuery* navQuery)
{
    if (npath < 3)
        return npath;

    // Get connected polygons
    static const int maxNeis = 16;
    dtPolyRef neis[maxNeis];
    int nneis = 0;

    const dtMeshTile* tile = 0;
    const dtPoly* poly = 0;
    if (dtStatusFailed(navQuery->getAttachedNavMesh()->getTileAndPolyByRef(path[0], &tile, &poly)))
        return npath;
    
    for (unsigned int k = poly->firstLink; k != DT_NULL_LINK; k = tile->links[k].next)
    {
        const dtLink* link = &tile->links[k];
        if (link->ref != 0)
        {
            if (nneis < maxNeis)
                neis[nneis++] = link->ref;
        }
    }

    // If any of the neighbour polygons is within the next few polygons
    // in the path, short cut to that polygon directly.
    static const int maxLookAhead = 6;
    int cut = 0;
    for (int i = dtMin(maxLookAhead, npath) - 1; i > 1 && cut == 0; i--) {
        for (int j = 0; j < nneis; j++)
        {
            if (path[i] == neis[j]) {
                cut = i;
                break;
            }
        }
    }
    if (cut > 1)
    {
        int offset = cut-1;
        npath -= offset;
        for (int i = 1; i < npath; i++)
            path[i] = path[i+offset];
    }

    return npath;
}

static bool getSteerTarget(dtNavMeshQuery* navQuery, const float* startPos, const float* endPos,
                           const float minTargetDist,
                           const dtPolyRef* path, const int pathSize,
                           float* steerPos, unsigned char& steerPosFlag, dtPolyRef& steerPosRef,
                           float* outPoints = 0, int* outPointCount = 0)                             
{
    // Find steer target.
    static const int MAX_STEER_POINTS = 3;
    float steerPath[MAX_STEER_POINTS*3];
    unsigned char steerPathFlags[MAX_STEER_POINTS];
    dtPolyRef steerPathPolys[MAX_STEER_POINTS];
    int nsteerPath = 0;
    navQuery->findStraightPath(startPos, endPos, path, pathSize,
                               steerPath, steerPathFlags, steerPathPolys, &nsteerPath, MAX_STEER_POINTS);
    if (!nsteerPath)
        return false;
        
    if (outPoints && outPointCount)
    {
        *outPointCount = nsteerPath;
        for (int i = 0; i < nsteerPath; ++i)
            dtVcopy(&outPoints[i*3], &steerPath[i*3]);
    }

    
    // Find vertex far enough to steer to.
    int ns = 0;
    while (ns < nsteerPath)
    {
        // Stop at Off-Mesh link or when point is further than slop away.
        if ((steerPathFlags[ns] & DT_STRAIGHTPATH_OFFMESH_CONNECTION) ||
            !inRange(&steerPath[ns*3], startPos, minTargetDist, 1000.0f))
            break;
        ns++;
    }
    // Failed to find good point to steer to.
    if (ns >= nsteerPath)
        return false;
    
    dtVcopy(steerPos, &steerPath[ns*3]);
    steerPos[1] = startPos[1];
    steerPosFlag = steerPathFlags[ns];
    steerPosRef = steerPathPolys[ns];
    
    return true;
}


NavMeshTesterTool::NavMeshTesterTool() :
    m_sample(0),
    m_navMesh(0),
    m_navQuery(0),
    m_pathFindStatus(DT_FAILURE),
    m_toolMode(TOOLMODE_PATHFIND_FOLLOW),
    m_straightPathOptions(0),
    m_startRef(0),
    m_endRef(0),
    m_npolys(0),
    m_nstraightPath(0),
    m_nsmoothPath(0),
    m_nrandPoints(0),
    m_randPointsInCircle(false),
    m_hitResult(false),
    m_distanceToWall(0),
    m_sposSet(false),
    m_eposSet(false),
    m_pathIterNum(0),
    m_steerPointCount(0)
{
    m_filter.setIncludeFlags(SAMPLE_POLYFLAGS_ALL ^ SAMPLE_POLYFLAGS_DISABLED);
    m_filter.setExcludeFlags(0);

    m_polyPickExt[0] = 2;
    m_polyPickExt[1] = 4;
    m_polyPickExt[2] = 2;
    
    m_neighbourhoodRadius = 2.5f;
    m_randomRadius = 5.0f;
}

NavMeshTesterTool::~NavMeshTesterTool()
{
}

void NavMeshTesterTool::init(Sample* sample)
{
    m_sample = sample;
    m_navMesh = sample->getNavMesh();
    m_navQuery = sample->getNavMeshQuery();
    recalc();

    if (m_navQuery)
    {
        // Change costs.
        m_filter.setAreaCost(SAMPLE_POLYAREA_GROUND, 1.0f);
        m_filter.setAreaCost(SAMPLE_POLYAREA_WATER, 10.0f);
        m_filter.setAreaCost(SAMPLE_POLYAREA_ROAD, 1.0f);
        m_filter.setAreaCost(SAMPLE_POLYAREA_DOOR, 1.0f);
        m_filter.setAreaCost(SAMPLE_POLYAREA_GRASS, 2.0f);
        m_filter.setAreaCost(SAMPLE_POLYAREA_JUMP, 1.5f);
    }
    
    m_neighbourhoodRadius = sample->getAgentRadius() * 20.0f;
    m_randomRadius = sample->getAgentRadius() * 30.0f;
}

void NavMeshTesterTool::handleMenu()
{
    if (imguiCheck("Pathfind Follow", m_toolMode == TOOLMODE_PATHFIND_FOLLOW))
    {
        m_toolMode = TOOLMODE_PATHFIND_FOLLOW;
        recalc();
    }
    if (imguiCheck("Pathfind Straight", m_toolMode == TOOLMODE_PATHFIND_STRAIGHT))
    {
        m_toolMode = TOOLMODE_PATHFIND_STRAIGHT;
        recalc();
    }
    if (m_toolMode == TOOLMODE_PATHFIND_STRAIGHT)
    {
        imguiIndent();
        imguiLabel("Vertices at crossings");
        if (imguiCheck("None", m_straightPathOptions == 0))
        {
            m_straightPathOptions = 0;
            recalc();
        }
        if (imguiCheck("Area", m_straightPathOptions == DT_STRAIGHTPATH_AREA_CROSSINGS))
        {
            m_straightPathOptions = DT_STRAIGHTPATH_AREA_CROSSINGS;
            recalc();
        }
        if (imguiCheck("All", m_straightPathOptions == DT_STRAIGHTPATH_ALL_CROSSINGS))
        {
            m_straightPathOptions = DT_STRAIGHTPATH_ALL_CROSSINGS;
            recalc();
        }

        imguiUnindent();
    }
    if (imguiCheck("Pathfind Sliced", m_toolMode == TOOLMODE_PATHFIND_SLICED))
    {
        m_toolMode = TOOLMODE_PATHFIND_SLICED;
        recalc();
    }

    imguiSeparator();

    if (imguiCheck("Distance to Wall", m_toolMode == TOOLMODE_DISTANCE_TO_WALL))
    {
        m_toolMode = TOOLMODE_DISTANCE_TO_WALL;
        recalc();
    }

    imguiSeparator();

    if (imguiCheck("Raycast", m_toolMode == TOOLMODE_RAYCAST))
    {
        m_toolMode = TOOLMODE_RAYCAST;
        recalc();
    }

    imguiSeparator();

    if (imguiCheck("Find Polys in Circle", m_toolMode == TOOLMODE_FIND_POLYS_IN_CIRCLE))
    {
        m_toolMode = TOOLMODE_FIND_POLYS_IN_CIRCLE;
        recalc();
    }
    if (imguiCheck("Find Polys in Shape", m_toolMode == TOOLMODE_FIND_POLYS_IN_SHAPE))
    {
        m_toolMode = TOOLMODE_FIND_POLYS_IN_SHAPE;
        recalc();
    }

    imguiSeparator();

    if (imguiCheck("Find Local Neighbourhood", m_toolMode == TOOLMODE_FIND_LOCAL_NEIGHBOURHOOD))
    {
        m_toolMode = TOOLMODE_FIND_LOCAL_NEIGHBOURHOOD;
        recalc();
    }

    imguiSeparator();
    
    if (imguiButton("Set Random Start"))
    {
        dtStatus status = m_navQuery->findRandomPoint(&m_filter, frand, &m_startRef, m_spos);
        if (dtStatusSucceed(status))
        {
            m_sposSet = true;
            recalc();
        }
    }
    if (imguiButton("Set Random End", m_sposSet))
    {
        if (m_sposSet)
        {
            dtStatus status = m_navQuery->findRandomPointAroundCircle(m_startRef, m_spos, m_randomRadius, &m_filter, frand, &m_endRef, m_epos);
            if (dtStatusSucceed(status))
            {
                m_eposSet = true;
                recalc();
            }
        }
    }

    imguiSeparator();

    if (imguiButton("Make Random Points"))
    {
        m_randPointsInCircle = false;
        m_nrandPoints = 0;
        for (int i = 0; i < MAX_RAND_POINTS; i++)
        {
            float pt[3];
            dtPolyRef ref;
            dtStatus status = m_navQuery->findRandomPoint(&m_filter, frand, &ref, pt);
            if (dtStatusSucceed(status))
            {
                dtVcopy(&m_randPoints[m_nrandPoints*3], pt);
                m_nrandPoints++;
            }
        }
    }
    if (imguiButton("Make Random Points Around", m_sposSet))
    {
        if (m_sposSet)
        {
            m_nrandPoints = 0;
            m_randPointsInCircle = true;
            for (int i = 0; i < MAX_RAND_POINTS; i++)
            {
                float pt[3];
                dtPolyRef ref;
                dtStatus status = m_navQuery->findRandomPointAroundCircle(m_startRef, m_spos, m_randomRadius, &m_filter, frand, &ref, pt);
                if (dtStatusSucceed(status))
                {
                    dtVcopy(&m_randPoints[m_nrandPoints*3], pt);
                    m_nrandPoints++;
                }
            }
        }
    }

    
    imguiSeparator();

    imguiLabel("Include Flags");

    imguiIndent();
    if (imguiCheck("Walk", (m_filter.getIncludeFlags() & SAMPLE_POLYFLAGS_WALK) != 0))
    {
        m_filter.setIncludeFlags(m_filter.getIncludeFlags() ^ SAMPLE_POLYFLAGS_WALK);
        recalc();
    }
    if (imguiCheck("Swim", (m_filter.getIncludeFlags() & SAMPLE_POLYFLAGS_SWIM) != 0))
    {
        m_filter.setIncludeFlags(m_filter.getIncludeFlags() ^ SAMPLE_POLYFLAGS_SWIM);
        recalc();
    }
    if (imguiCheck("Door", (m_filter.getIncludeFlags() & SAMPLE_POLYFLAGS_DOOR) != 0))
    {
        m_filter.setIncludeFlags(m_filter.getIncludeFlags() ^ SAMPLE_POLYFLAGS_DOOR);
        recalc();
    }
    if (imguiCheck("Jump", (m_filter.getIncludeFlags() & SAMPLE_POLYFLAGS_JUMP) != 0))
    {
        m_filter.setIncludeFlags(m_filter.getIncludeFlags() ^ SAMPLE_POLYFLAGS_JUMP);
        recalc();
    }
    imguiUnindent();

    imguiSeparator();
    imguiLabel("Exclude Flags");
    
    imguiIndent();
    if (imguiCheck("Walk", (m_filter.getExcludeFlags() & SAMPLE_POLYFLAGS_WALK) != 0))
    {
        m_filter.setExcludeFlags(m_filter.getExcludeFlags() ^ SAMPLE_POLYFLAGS_WALK);
        recalc();
    }
    if (imguiCheck("Swim", (m_filter.getExcludeFlags() & SAMPLE_POLYFLAGS_SWIM) != 0))
    {
        m_filter.setExcludeFlags(m_filter.getExcludeFlags() ^ SAMPLE_POLYFLAGS_SWIM);
        recalc();
    }
    if (imguiCheck("Door", (m_filter.getExcludeFlags() & SAMPLE_POLYFLAGS_DOOR) != 0))
    {
        m_filter.setExcludeFlags(m_filter.getExcludeFlags() ^ SAMPLE_POLYFLAGS_DOOR);
        recalc();
    }
    if (imguiCheck("Jump", (m_filter.getExcludeFlags() & SAMPLE_POLYFLAGS_JUMP) != 0))
    {
        m_filter.setExcludeFlags(m_filter.getExcludeFlags() ^ SAMPLE_POLYFLAGS_JUMP);
        recalc();
    }
    imguiUnindent();

    imguiSeparator();    
}

void NavMeshTesterTool::handleClick(const float* /*s*/, const float* p, bool shift)
{
    if (shift)
    {
        m_sposSet = true;
        dtVcopy(m_spos, p);
    }
    else
    {
        m_eposSet = true;
        dtVcopy(m_epos, p);
    }
    recalc();
}

void NavMeshTesterTool::handleStep()
{
}

void NavMeshTesterTool::handleToggle()
{
    // TODO: merge separate to a path iterator. Use same code in recalc() too.
    if (m_toolMode != TOOLMODE_PATHFIND_FOLLOW)
        return;
        
    if (!m_sposSet || !m_eposSet || !m_startRef || !m_endRef)
        return;
        
    static const float STEP_SIZE = 0.5f;
    static const float SLOP = 0.01f;

    if (m_pathIterNum == 0)
    {
        m_navQuery->findPath(m_startRef, m_endRef, m_spos, m_epos, &m_filter, m_polys, &m_npolys, MAX_POLYS);
        m_nsmoothPath = 0;

        m_pathIterPolyCount = m_npolys;
        if (m_pathIterPolyCount)
            memcpy(m_pathIterPolys, m_polys, sizeof(dtPolyRef)*m_pathIterPolyCount); 
        
        if (m_pathIterPolyCount)
        {
            // Iterate over the path to find smooth path on the detail mesh surface.
            m_navQuery->closestPointOnPoly(m_startRef, m_spos, m_iterPos, 0);
            m_navQuery->closestPointOnPoly(m_pathIterPolys[m_pathIterPolyCount-1], m_epos, m_targetPos, 0);
            
            m_nsmoothPath = 0;
            
            dtVcopy(&m_smoothPath[m_nsmoothPath*3], m_iterPos);
            m_nsmoothPath++;
        }
    }
    
    dtVcopy(m_prevIterPos, m_iterPos);

    m_pathIterNum++;

    if (!m_pathIterPolyCount)
        return;

    if (m_nsmoothPath >= MAX_SMOOTH)
        return;

    // Move towards target a small advancement at a time until target reached or
    // when ran out of memory to store the path.

    // Find location to steer towards.
    float steerPos[3];
    unsigned char steerPosFlag;
    dtPolyRef steerPosRef;
        
    if (!getSteerTarget(m_navQuery, m_iterPos, m_targetPos, SLOP,
                        m_pathIterPolys, m_pathIterPolyCount, steerPos, steerPosFlag, steerPosRef,
                        m_steerPoints, &m_steerPointCount))
        return;
        
    dtVcopy(m_steerPos, steerPos);
    
    bool endOfPath = (steerPosFlag & DT_STRAIGHTPATH_END) ? true : false;
    bool offMeshConnection = (steerPosFlag & DT_STRAIGHTPATH_OFFMESH_CONNECTION) ? true : false;
        
    // Find movement delta.
    float delta[3], len;
    dtVsub(delta, steerPos, m_iterPos);
    len = sqrtf(dtVdot(delta,delta));
    // If the steer target is end of path or off-mesh link, do not move past the location.
    if ((endOfPath || offMeshConnection) && len < STEP_SIZE)
        len = 1;
    else
        len = STEP_SIZE / len;
    float moveTgt[3];
    dtVmad(moveTgt, m_iterPos, delta, len);
        
    // Move
    float result[3];
    dtPolyRef visited[16];
    int nvisited = 0;
    m_navQuery->moveAlongSurface(m_pathIterPolys[0], m_iterPos, moveTgt, &m_filter,
                                 result, visited, &nvisited, 16);
    m_pathIterPolyCount = fixupCorridor(m_pathIterPolys, m_pathIterPolyCount, MAX_POLYS, visited, nvisited);
    m_pathIterPolyCount = fixupShortcuts(m_pathIterPolys, m_pathIterPolyCount, m_navQuery);

    float h = 0;
    m_navQuery->getPolyHeight(m_pathIterPolys[0], result, &h);
    result[1] = h;
    dtVcopy(m_iterPos, result);
    
    // Handle end of path and off-mesh links when close enough.
    if (endOfPath && inRange(m_iterPos, steerPos, SLOP, 1.0f))
    {
        // Reached end of path.
        dtVcopy(m_iterPos, m_targetPos);
        if (m_nsmoothPath < MAX_SMOOTH)
        {
            dtVcopy(&m_smoothPath[m_nsmoothPath*3], m_iterPos);
            m_nsmoothPath++;
        }
        return;
    }
    else if (offMeshConnection && inRange(m_iterPos, steerPos, SLOP, 1.0f))
    {
        // Reached off-mesh connection.
        float startPos[3], endPos[3];
        
        // Advance the path up to and over the off-mesh connection.
        dtPolyRef prevRef = 0, polyRef = m_pathIterPolys[0];
        int npos = 0;
        while (npos < m_pathIterPolyCount && polyRef != steerPosRef)
        {
            prevRef = polyRef;
            polyRef = m_pathIterPolys[npos];
            npos++;
        }
        for (int i = npos; i < m_pathIterPolyCount; ++i)
            m_pathIterPolys[i-npos] = m_pathIterPolys[i];
        m_pathIterPolyCount -= npos;
                
        // Handle the connection.
        dtStatus status = m_navMesh->getOffMeshConnectionPolyEndPoints(prevRef, polyRef, startPos, endPos);
        if (dtStatusSucceed(status))
        {
            if (m_nsmoothPath < MAX_SMOOTH)
            {
                dtVcopy(&m_smoothPath[m_nsmoothPath*3], startPos);
                m_nsmoothPath++;
                // Hack to make the dotted path not visible during off-mesh connection.
                if (m_nsmoothPath & 1)
                {
                    dtVcopy(&m_smoothPath[m_nsmoothPath*3], startPos);
                    m_nsmoothPath++;
                }
            }
            // Move position at the other side of the off-mesh link.
            dtVcopy(m_iterPos, endPos);
            float eh = 0.0f;
            m_navQuery->getPolyHeight(m_pathIterPolys[0], m_iterPos, &eh);
            m_iterPos[1] = eh;
        }
    }
    
    // Store results.
    if (m_nsmoothPath < MAX_SMOOTH)
    {
        dtVcopy(&m_smoothPath[m_nsmoothPath*3], m_iterPos);
        m_nsmoothPath++;
    }

}

void NavMeshTesterTool::handleUpdate(const float /*dt*/)
{
    if (m_toolMode == TOOLMODE_PATHFIND_SLICED)
    {
        if (dtStatusInProgress(m_pathFindStatus))
        {
            m_pathFindStatus = m_navQuery->updateSlicedFindPath(1,0);
        }
        if (dtStatusSucceed(m_pathFindStatus))
        {
            m_navQuery->finalizeSlicedFindPath(m_polys, &m_npolys, MAX_POLYS);
            m_nstraightPath = 0;
            if (m_npolys)
            {
                // In case of partial path, make sure the end point is clamped to the last polygon.
                float epos[3];
                dtVcopy(epos, m_epos);
                if (m_polys[m_npolys-1] != m_endRef)
                m_navQuery->closestPointOnPoly(m_polys[m_npolys-1], m_epos, epos, 0);

                m_navQuery->findStraightPath(m_spos, epos, m_polys, m_npolys,
                                             m_straightPath, m_straightPathFlags,
                                             m_straightPathPolys, &m_nstraightPath, MAX_POLYS, DT_STRAIGHTPATH_ALL_CROSSINGS);
            }
             
            m_pathFindStatus = DT_FAILURE;
        }
    }
}

void NavMeshTesterTool::reset()
{
    m_startRef = 0;
    m_endRef = 0;
    m_npolys = 0;
    m_nstraightPath = 0;
    m_nsmoothPath = 0;
    memset(m_hitPos, 0, sizeof(m_hitPos));
    memset(m_hitNormal, 0, sizeof(m_hitNormal));
    m_distanceToWall = 0;
}


void NavMeshTesterTool::recalc()
{
    if (!m_navMesh)
        return;
    
    if (m_sposSet)
        m_navQuery->findNearestPoly(m_spos, m_polyPickExt, &m_filter, &m_startRef, 0);
    else
        m_startRef = 0;
    
    if (m_eposSet)
        m_navQuery->findNearestPoly(m_epos, m_polyPickExt, &m_filter, &m_endRef, 0);
    else
        m_endRef = 0;
    
    m_pathFindStatus = DT_FAILURE;
    
    if (m_toolMode == TOOLMODE_PATHFIND_FOLLOW)
    {
        m_pathIterNum = 0;
        if (m_sposSet && m_eposSet && m_startRef && m_endRef)
        {
#ifdef DUMP_REQS
            printf("pi  %f %f %f  %f %f %f  0x%x 0x%x\n",
                   m_spos[0],m_spos[1],m_spos[2], m_epos[0],m_epos[1],m_epos[2],
                   m_filter.getIncludeFlags(), m_filter.getExcludeFlags()); 
#endif

            m_navQuery->findPath(m_startRef, m_endRef, m_spos, m_epos, &m_filter, m_polys, &m_npolys, MAX_POLYS);

            m_nsmoothPath = 0;

            if (m_npolys)
            {
                // Iterate over the path to find smooth path on the detail mesh surface.
                dtPolyRef polys[MAX_POLYS];
                memcpy(polys, m_polys, sizeof(dtPolyRef)*m_npolys); 
                int npolys = m_npolys;
                
                float iterPos[3], targetPos[3];
                m_navQuery->closestPointOnPoly(m_startRef, m_spos, iterPos, 0);
                m_navQuery->closestPointOnPoly(polys[npolys-1], m_epos, targetPos, 0);
                
                static const float STEP_SIZE = 0.5f;
                static const float SLOP = 0.01f;
                
                m_nsmoothPath = 0;
                
                dtVcopy(&m_smoothPath[m_nsmoothPath*3], iterPos);
                m_nsmoothPath++;
                
                // Move towards target a small advancement at a time until target reached or
                // when ran out of memory to store the path.
                while (npolys && m_nsmoothPath < MAX_SMOOTH)
                {
                    // Find location to steer towards.
                    float steerPos[3];
                    unsigned char steerPosFlag;
                    dtPolyRef steerPosRef;
                    
                    if (!getSteerTarget(m_navQuery, iterPos, targetPos, SLOP,
                                        polys, npolys, steerPos, steerPosFlag, steerPosRef))
                        break;
                    
                    bool endOfPath = (steerPosFlag & DT_STRAIGHTPATH_END) ? true : false;
                    bool offMeshConnection = (steerPosFlag & DT_STRAIGHTPATH_OFFMESH_CONNECTION) ? true : false;
                    
                    // Find movement delta.
                    float delta[3], len;
                    dtVsub(delta, steerPos, iterPos);
                    len = dtSqrt(dtVdot(delta,delta));
                    // If the steer target is end of path or off-mesh link, do not move past the location.
                    if ((endOfPath || offMeshConnection) && len < STEP_SIZE)
                        len = 1;
                    else
                        len = STEP_SIZE / len;
                    float moveTgt[3];
                    dtVmad(moveTgt, iterPos, delta, len);
                    
                    // Move
                    float result[3];
                    dtPolyRef visited[16];
                    int nvisited = 0;
                    m_navQuery->moveAlongSurface(polys[0], iterPos, moveTgt, &m_filter,
                                                 result, visited, &nvisited, 16);

                    npolys = fixupCorridor(polys, npolys, MAX_POLYS, visited, nvisited);
                    npolys = fixupShortcuts(polys, npolys, m_navQuery);

                    float h = 0;
                    m_navQuery->getPolyHeight(polys[0], result, &h);
                    result[1] = h;
                    dtVcopy(iterPos, result);

                    // Handle end of path and off-mesh links when close enough.
                    if (endOfPath && inRange(iterPos, steerPos, SLOP, 1.0f))
                    {
                        // Reached end of path.
                        dtVcopy(iterPos, targetPos);
                        if (m_nsmoothPath < MAX_SMOOTH)
                        {
                            dtVcopy(&m_smoothPath[m_nsmoothPath*3], iterPos);
                            m_nsmoothPath++;
                        }
                        break;
                    }
                    else if (offMeshConnection && inRange(iterPos, steerPos, SLOP, 1.0f))
                    {
                        // Reached off-mesh connection.
                        float startPos[3], endPos[3];
                        
                        // Advance the path up to and over the off-mesh connection.
                        dtPolyRef prevRef = 0, polyRef = polys[0];
                        int npos = 0;
                        while (npos < npolys && polyRef != steerPosRef)
                        {
                            prevRef = polyRef;
                            polyRef = polys[npos];
                            npos++;
                        }
                        for (int i = npos; i < npolys; ++i)
                            polys[i-npos] = polys[i];
                        npolys -= npos;
                        
                        // Handle the connection.
                        dtStatus status = m_navMesh->getOffMeshConnectionPolyEndPoints(prevRef, polyRef, startPos, endPos);
                        if (dtStatusSucceed(status))
                        {
                            if (m_nsmoothPath < MAX_SMOOTH)
                            {
                                dtVcopy(&m_smoothPath[m_nsmoothPath*3], startPos);
                                m_nsmoothPath++;
                                // Hack to make the dotted path not visible during off-mesh connection.
                                if (m_nsmoothPath & 1)
                                {
                                    dtVcopy(&m_smoothPath[m_nsmoothPath*3], startPos);
                                    m_nsmoothPath++;
                                }
                            }
                            // Move position at the other side of the off-mesh link.
                            dtVcopy(iterPos, endPos);
                            float eh = 0.0f;
                            m_navQuery->getPolyHeight(polys[0], iterPos, &eh);
                            iterPos[1] = eh;
                        }
                    }
                    
                    // Store results.
                    if (m_nsmoothPath < MAX_SMOOTH)
                    {
                        dtVcopy(&m_smoothPath[m_nsmoothPath*3], iterPos);
                        m_nsmoothPath++;
                    }
                }
            }

        }
        else
        {
            m_npolys = 0;
            m_nsmoothPath = 0;
        }
    }
    else if (m_toolMode == TOOLMODE_PATHFIND_STRAIGHT)
    {
        if (m_sposSet && m_eposSet && m_startRef && m_endRef)
        {
#ifdef DUMP_REQS
            printf("ps  %f %f %f  %f %f %f  0x%x 0x%x\n",
                   m_spos[0],m_spos[1],m_spos[2], m_epos[0],m_epos[1],m_epos[2],
                   m_filter.getIncludeFlags(), m_filter.getExcludeFlags()); 
#endif
            m_navQuery->findPath(m_startRef, m_endRef, m_spos, m_epos, &m_filter, m_polys, &m_npolys, MAX_POLYS);
            m_nstraightPath = 0;
            if (m_npolys)
            {
                // In case of partial path, make sure the end point is clamped to the last polygon.
                float epos[3];
                dtVcopy(epos, m_epos);
                if (m_polys[m_npolys-1] != m_endRef)
                    m_navQuery->closestPointOnPoly(m_polys[m_npolys-1], m_epos, epos, 0);
                
                m_navQuery->findStraightPath(m_spos, epos, m_polys, m_npolys,
                                             m_straightPath, m_straightPathFlags,
                                             m_straightPathPolys, &m_nstraightPath, MAX_POLYS, m_straightPathOptions);
            }
        }
        else
        {
            m_npolys = 0;
            m_nstraightPath = 0;
        }
    }
    else if (m_toolMode == TOOLMODE_PATHFIND_SLICED)
    {
        if (m_sposSet && m_eposSet && m_startRef && m_endRef)
        {
#ifdef DUMP_REQS
            printf("ps  %f %f %f  %f %f %f  0x%x 0x%x\n",
                   m_spos[0],m_spos[1],m_spos[2], m_epos[0],m_epos[1],m_epos[2],
                   m_filter.getIncludeFlags(), m_filter.getExcludeFlags()); 
#endif
            m_npolys = 0;
            m_nstraightPath = 0;
            
            m_pathFindStatus = m_navQuery->initSlicedFindPath(m_startRef, m_endRef, m_spos, m_epos, &m_filter, DT_FINDPATH_ANY_ANGLE);
        }
        else
        {
            m_npolys = 0;
            m_nstraightPath = 0;
        }
    }
    else if (m_toolMode == TOOLMODE_RAYCAST)
    {
        m_nstraightPath = 0;
        if (m_sposSet && m_eposSet && m_startRef)
        {
#ifdef DUMP_REQS
            printf("rc  %f %f %f  %f %f %f  0x%x 0x%x\n",
                   m_spos[0],m_spos[1],m_spos[2], m_epos[0],m_epos[1],m_epos[2],
                   m_filter.getIncludeFlags(), m_filter.getExcludeFlags()); 
#endif
            float t = 0;
            m_npolys = 0;
            m_nstraightPath = 2;
            m_straightPath[0] = m_spos[0];
            m_straightPath[1] = m_spos[1];
            m_straightPath[2] = m_spos[2];
            m_navQuery->raycast(m_startRef, m_spos, m_epos, &m_filter, &t, m_hitNormal, m_polys, &m_npolys, MAX_POLYS);
            if (t > 1)
            {
                // No hit
                dtVcopy(m_hitPos, m_epos);
                m_hitResult = false;
            }
            else
            {
                // Hit
                dtVlerp(m_hitPos, m_spos, m_epos, t);
                m_hitResult = true;
            }
            // Adjust height.
            if (m_npolys > 0)
            {
                float h = 0;
                m_navQuery->getPolyHeight(m_polys[m_npolys-1], m_hitPos, &h);
                m_hitPos[1] = h;
            }
            dtVcopy(&m_straightPath[3], m_hitPos);
        }
    }
    else if (m_toolMode == TOOLMODE_DISTANCE_TO_WALL)
    {
        m_distanceToWall = 0;
        if (m_sposSet && m_startRef)
        {
#ifdef DUMP_REQS
            printf("dw  %f %f %f  %f  0x%x 0x%x\n",
                   m_spos[0],m_spos[1],m_spos[2], 100.0f,
                   m_filter.getIncludeFlags(), m_filter.getExcludeFlags()); 
#endif
            m_distanceToWall = 0.0f;
            m_navQuery->findDistanceToWall(m_startRef, m_spos, 100.0f, &m_filter, &m_distanceToWall, m_hitPos, m_hitNormal);
        }
    }
    else if (m_toolMode == TOOLMODE_FIND_POLYS_IN_CIRCLE)
    {
        if (m_sposSet && m_startRef && m_eposSet)
        {
            const float dx = m_epos[0] - m_spos[0];
            const float dz = m_epos[2] - m_spos[2];
            float dist = sqrtf(dx*dx + dz*dz);
#ifdef DUMP_REQS
            printf("fpc  %f %f %f  %f  0x%x 0x%x\n",
                   m_spos[0],m_spos[1],m_spos[2], dist,
                   m_filter.getIncludeFlags(), m_filter.getExcludeFlags());
#endif
            m_navQuery->findPolysAroundCircle(m_startRef, m_spos, dist, &m_filter,
                                              m_polys, m_parent, 0, &m_npolys, MAX_POLYS);

        }
    }
    else if (m_toolMode == TOOLMODE_FIND_POLYS_IN_SHAPE)
    {
        if (m_sposSet && m_startRef && m_eposSet)
        {
            const float nx = (m_epos[2] - m_spos[2])*0.25f;
            const float nz = -(m_epos[0] - m_spos[0])*0.25f;
            const float agentHeight = m_sample ? m_sample->getAgentHeight() : 0;

            m_queryPoly[0] = m_spos[0] + nx*1.2f;
            m_queryPoly[1] = m_spos[1] + agentHeight/2;
            m_queryPoly[2] = m_spos[2] + nz*1.2f;

            m_queryPoly[3] = m_spos[0] - nx*1.3f;
            m_queryPoly[4] = m_spos[1] + agentHeight/2;
            m_queryPoly[5] = m_spos[2] - nz*1.3f;

            m_queryPoly[6] = m_epos[0] - nx*0.8f;
            m_queryPoly[7] = m_epos[1] + agentHeight/2;
            m_queryPoly[8] = m_epos[2] - nz*0.8f;

            m_queryPoly[9] = m_epos[0] + nx;
            m_queryPoly[10] = m_epos[1] + agentHeight/2;
            m_queryPoly[11] = m_epos[2] + nz;
            
#ifdef DUMP_REQS
            printf("fpp  %f %f %f  %f %f %f  %f %f %f  %f %f %f  0x%x 0x%x\n",
                   m_queryPoly[0],m_queryPoly[1],m_queryPoly[2],
                   m_queryPoly[3],m_queryPoly[4],m_queryPoly[5],
                   m_queryPoly[6],m_queryPoly[7],m_queryPoly[8],
                   m_queryPoly[9],m_queryPoly[10],m_queryPoly[11],
                   m_filter.getIncludeFlags(), m_filter.getExcludeFlags());
#endif
            m_navQuery->findPolysAroundShape(m_startRef, m_queryPoly, 4, &m_filter,
                                             m_polys, m_parent, 0, &m_npolys, MAX_POLYS);
        }
    }
    else if (m_toolMode == TOOLMODE_FIND_LOCAL_NEIGHBOURHOOD)
    {
        if (m_sposSet && m_startRef)
        {
#ifdef DUMP_REQS
            printf("fln  %f %f %f  %f  0x%x 0x%x\n",
                   m_spos[0],m_spos[1],m_spos[2], m_neighbourhoodRadius,
                   m_filter.getIncludeFlags(), m_filter.getExcludeFlags());
#endif
            m_navQuery->findLocalNeighbourhood(m_startRef, m_spos, m_neighbourhoodRadius, &m_filter,
                                               m_polys, m_parent, &m_npolys, MAX_POLYS);
        }
    }
}

static void getPolyCenter(dtNavMesh* navMesh, dtPolyRef ref, float* center)
{
    center[0] = 0;
    center[1] = 0;
    center[2] = 0;
    
    const dtMeshTile* tile = 0;
    const dtPoly* poly = 0;
    dtStatus status = navMesh->getTileAndPolyByRef(ref, &tile, &poly);
    if (dtStatusFailed(status))
        return;
        
    for (int i = 0; i < (int)poly->vertCount; ++i)
    {
        const float* v = &tile->verts[poly->verts[i]*3];
        center[0] += v[0];
        center[1] += v[1];
        center[2] += v[2];
    }
    const float s = 1.0f / poly->vertCount;
    center[0] *= s;
    center[1] *= s;
    center[2] *= s;
}



void NavMeshTesterTool::handleRender()
{
    DebugDrawGL dd;
    
    static const unsigned int startCol = duRGBA(128,25,0,192);
    static const unsigned int endCol = duRGBA(51,102,0,129);
    static const unsigned int pathCol = duRGBA(0,0,0,64);
    
    const float agentRadius = m_sample->getAgentRadius();
    const float agentHeight = m_sample->getAgentHeight();
    const float agentClimb = m_sample->getAgentClimb();
    
    dd.depthMask(false);
    if (m_sposSet)
        drawAgent(m_spos, agentRadius, agentHeight, agentClimb, startCol);
    if (m_eposSet)
        drawAgent(m_epos, agentRadius, agentHeight, agentClimb, endCol);
    dd.depthMask(true);
    
    if (!m_navMesh)
    {
        return;
    }

    if (m_toolMode == TOOLMODE_PATHFIND_FOLLOW)
    {
        duDebugDrawNavMeshPoly(&dd, *m_navMesh, m_startRef, startCol);
        duDebugDrawNavMeshPoly(&dd, *m_navMesh, m_endRef, endCol);
        
        if (m_npolys)
        {
            for (int i = 0; i < m_npolys; ++i)
            {
                if (m_polys[i] == m_startRef || m_polys[i] == m_endRef)
                    continue;
                duDebugDrawNavMeshPoly(&dd, *m_navMesh, m_polys[i], pathCol);
            }
        }
                
        if (m_nsmoothPath)
        {
            dd.depthMask(false);
            const unsigned int spathCol = duRGBA(0,0,0,220);
            dd.begin(DU_DRAW_LINES, 3.0f);
            for (int i = 0; i < m_nsmoothPath; ++i)
                dd.vertex(m_smoothPath[i*3], m_smoothPath[i*3+1]+0.1f, m_smoothPath[i*3+2], spathCol);
            dd.end();
            dd.depthMask(true);
        }
        
        if (m_pathIterNum)
        {
            duDebugDrawNavMeshPoly(&dd, *m_navMesh, m_pathIterPolys[0], duRGBA(255,255,255,128));

            dd.depthMask(false);
            dd.begin(DU_DRAW_LINES, 1.0f);
            
            const unsigned int prevCol = duRGBA(255,192,0,220);
            const unsigned int curCol = duRGBA(255,255,255,220);
            const unsigned int steerCol = duRGBA(0,192,255,220);

            dd.vertex(m_prevIterPos[0],m_prevIterPos[1]-0.3f,m_prevIterPos[2], prevCol);
            dd.vertex(m_prevIterPos[0],m_prevIterPos[1]+0.3f,m_prevIterPos[2], prevCol);

            dd.vertex(m_iterPos[0],m_iterPos[1]-0.3f,m_iterPos[2], curCol);
            dd.vertex(m_iterPos[0],m_iterPos[1]+0.3f,m_iterPos[2], curCol);

            dd.vertex(m_prevIterPos[0],m_prevIterPos[1]+0.3f,m_prevIterPos[2], prevCol);
            dd.vertex(m_iterPos[0],m_iterPos[1]+0.3f,m_iterPos[2], prevCol);

            dd.vertex(m_prevIterPos[0],m_prevIterPos[1]+0.3f,m_prevIterPos[2], steerCol);
            dd.vertex(m_steerPos[0],m_steerPos[1]+0.3f,m_steerPos[2], steerCol);
            
            for (int i = 0; i < m_steerPointCount-1; ++i)
            {
                dd.vertex(m_steerPoints[i*3+0],m_steerPoints[i*3+1]+0.2f,m_steerPoints[i*3+2], duDarkenCol(steerCol));
                dd.vertex(m_steerPoints[(i+1)*3+0],m_steerPoints[(i+1)*3+1]+0.2f,m_steerPoints[(i+1)*3+2], duDarkenCol(steerCol));
            }
            
            dd.end();
            dd.depthMask(true);
        }
    }
    else if (m_toolMode == TOOLMODE_PATHFIND_STRAIGHT ||
             m_toolMode == TOOLMODE_PATHFIND_SLICED)
    {
        duDebugDrawNavMeshPoly(&dd, *m_navMesh, m_startRef, startCol);
        duDebugDrawNavMeshPoly(&dd, *m_navMesh, m_endRef, endCol);
        
        if (m_npolys)
        {
            for (int i = 0; i < m_npolys; ++i)
            {
                if (m_polys[i] == m_startRef || m_polys[i] == m_endRef)
                    continue;
                duDebugDrawNavMeshPoly(&dd, *m_navMesh, m_polys[i], pathCol);
            }
        }
        
        if (m_nstraightPath)
        {
            dd.depthMask(false);
            const unsigned int spathCol = duRGBA(64,16,0,220);
            const unsigned int offMeshCol = duRGBA(128,96,0,220);
            dd.begin(DU_DRAW_LINES, 2.0f);
            for (int i = 0; i < m_nstraightPath-1; ++i)
            {
                unsigned int col = 0;
                if (m_straightPathFlags[i] & DT_STRAIGHTPATH_OFFMESH_CONNECTION)
                    col = offMeshCol;
                else
                    col = spathCol;
                
                dd.vertex(m_straightPath[i*3], m_straightPath[i*3+1]+0.4f, m_straightPath[i*3+2], col);
                dd.vertex(m_straightPath[(i+1)*3], m_straightPath[(i+1)*3+1]+0.4f, m_straightPath[(i+1)*3+2], col);
            }
            dd.end();
            dd.begin(DU_DRAW_POINTS, 6.0f);
            for (int i = 0; i < m_nstraightPath; ++i)
            {
                unsigned int col = 0;
                if (m_straightPathFlags[i] & DT_STRAIGHTPATH_START)
                    col = startCol;
                else if (m_straightPathFlags[i] & DT_STRAIGHTPATH_START)
                    col = endCol;
                else if (m_straightPathFlags[i] & DT_STRAIGHTPATH_OFFMESH_CONNECTION)
                    col = offMeshCol;
                else
                    col = spathCol;
                dd.vertex(m_straightPath[i*3], m_straightPath[i*3+1]+0.4f, m_straightPath[i*3+2], col);
            }
            dd.end();
            dd.depthMask(true);
        }
    }
    else if (m_toolMode == TOOLMODE_RAYCAST)
    {
        duDebugDrawNavMeshPoly(&dd, *m_navMesh, m_startRef, startCol);
        
        if (m_nstraightPath)
        {
            for (int i = 1; i < m_npolys; ++i)
                duDebugDrawNavMeshPoly(&dd, *m_navMesh, m_polys[i], pathCol);
            
            dd.depthMask(false);
            const unsigned int spathCol = m_hitResult ? duRGBA(64,16,0,220) : duRGBA(240,240,240,220);
            dd.begin(DU_DRAW_LINES, 2.0f);
            for (int i = 0; i < m_nstraightPath-1; ++i)
            {
                dd.vertex(m_straightPath[i*3], m_straightPath[i*3+1]+0.4f, m_straightPath[i*3+2], spathCol);
                dd.vertex(m_straightPath[(i+1)*3], m_straightPath[(i+1)*3+1]+0.4f, m_straightPath[(i+1)*3+2], spathCol);
            }
            dd.end();
            dd.begin(DU_DRAW_POINTS, 4.0f);
            for (int i = 0; i < m_nstraightPath; ++i)
                dd.vertex(m_straightPath[i*3], m_straightPath[i*3+1]+0.4f, m_straightPath[i*3+2], spathCol);
            dd.end();

            if (m_hitResult)
            {
                const unsigned int hitCol = duRGBA(0,0,0,128);
                dd.begin(DU_DRAW_LINES, 2.0f);
                dd.vertex(m_hitPos[0], m_hitPos[1] + 0.4f, m_hitPos[2], hitCol);
                dd.vertex(m_hitPos[0] + m_hitNormal[0]*agentRadius,
                          m_hitPos[1] + 0.4f + m_hitNormal[1]*agentRadius,
                          m_hitPos[2] + m_hitNormal[2]*agentRadius, hitCol);
                dd.end();
            }
            dd.depthMask(true);
        }
    }
    else if (m_toolMode == TOOLMODE_DISTANCE_TO_WALL)
    {
        duDebugDrawNavMeshPoly(&dd, *m_navMesh, m_startRef, startCol);
        dd.depthMask(false);
        duDebugDrawCircle(&dd, m_spos[0], m_spos[1]+agentHeight/2, m_spos[2], m_distanceToWall, duRGBA(64,16,0,220), 2.0f);
        dd.begin(DU_DRAW_LINES, 3.0f);
        dd.vertex(m_hitPos[0], m_hitPos[1] + 0.02f, m_hitPos[2], duRGBA(0,0,0,192));
        dd.vertex(m_hitPos[0], m_hitPos[1] + agentHeight, m_hitPos[2], duRGBA(0,0,0,192));
        dd.end();
        dd.depthMask(true);
    }
    else if (m_toolMode == TOOLMODE_FIND_POLYS_IN_CIRCLE)
    {
        for (int i = 0; i < m_npolys; ++i)
        {
            duDebugDrawNavMeshPoly(&dd, *m_navMesh, m_polys[i], pathCol);
            dd.depthMask(false);
            if (m_parent[i])
            {
                float p0[3], p1[3];
                dd.depthMask(false);
                getPolyCenter(m_navMesh, m_parent[i], p0);
                getPolyCenter(m_navMesh, m_polys[i], p1);
                duDebugDrawArc(&dd, p0[0],p0[1],p0[2], p1[0],p1[1],p1[2], 0.25f, 0.0f, 0.4f, duRGBA(0,0,0,128), 2.0f);
                dd.depthMask(true);
            }
            dd.depthMask(true);
        }
        
        if (m_sposSet && m_eposSet)
        {
            dd.depthMask(false);
            const float dx = m_epos[0] - m_spos[0];
            const float dz = m_epos[2] - m_spos[2];
            const float dist = sqrtf(dx*dx + dz*dz);
            duDebugDrawCircle(&dd, m_spos[0], m_spos[1]+agentHeight/2, m_spos[2], dist, duRGBA(64,16,0,220), 2.0f);
            dd.depthMask(true);
        }
    }    
    else if (m_toolMode == TOOLMODE_FIND_POLYS_IN_SHAPE)
    {
        for (int i = 0; i < m_npolys; ++i)
        {
            duDebugDrawNavMeshPoly(&dd, *m_navMesh, m_polys[i], pathCol);
            dd.depthMask(false);
            if (m_parent[i])
            {
                float p0[3], p1[3];
                dd.depthMask(false);
                getPolyCenter(m_navMesh, m_parent[i], p0);
                getPolyCenter(m_navMesh, m_polys[i], p1);
                duDebugDrawArc(&dd, p0[0],p0[1],p0[2], p1[0],p1[1],p1[2], 0.25f, 0.0f, 0.4f, duRGBA(0,0,0,128), 2.0f);
                dd.depthMask(true);
            }
            dd.depthMask(true);
        }
        
        if (m_sposSet && m_eposSet)
        {
            dd.depthMask(false);
            const unsigned int col = duRGBA(64,16,0,220);
            dd.begin(DU_DRAW_LINES, 2.0f);
            for (int i = 0, j = 3; i < 4; j=i++)
            {
                const float* p0 = &m_queryPoly[j*3];
                const float* p1 = &m_queryPoly[i*3];
                dd.vertex(p0, col);
                dd.vertex(p1, col);
            }
            dd.end();
            dd.depthMask(true);
        }
    }
    else if (m_toolMode == TOOLMODE_FIND_LOCAL_NEIGHBOURHOOD)
    {
        for (int i = 0; i < m_npolys; ++i)
        {
            duDebugDrawNavMeshPoly(&dd, *m_navMesh, m_polys[i], pathCol);
            dd.depthMask(false);
            if (m_parent[i])
            {
                float p0[3], p1[3];
                dd.depthMask(false);
                getPolyCenter(m_navMesh, m_parent[i], p0);
                getPolyCenter(m_navMesh, m_polys[i], p1);
                duDebugDrawArc(&dd, p0[0],p0[1],p0[2], p1[0],p1[1],p1[2], 0.25f, 0.0f, 0.4f, duRGBA(0,0,0,128), 2.0f);
                dd.depthMask(true);
            }

            static const int MAX_SEGS = DT_VERTS_PER_POLYGON*4;
            float segs[MAX_SEGS*6];
            dtPolyRef refs[MAX_SEGS];
            memset(refs, 0, sizeof(dtPolyRef)*MAX_SEGS); 
            int nsegs = 0;
            m_navQuery->getPolyWallSegments(m_polys[i], &m_filter, segs, refs, &nsegs, MAX_SEGS);
            dd.begin(DU_DRAW_LINES, 2.0f);
            for (int j = 0; j < nsegs; ++j)
            {
                const float* s = &segs[j*6];
                
                // Skip too distant segments.
                float tseg;
                float distSqr = dtDistancePtSegSqr2D(m_spos, s, s+3, tseg);
                if (distSqr > dtSqr(m_neighbourhoodRadius))
                    continue;
                
                float delta[3], norm[3], p0[3], p1[3];
                dtVsub(delta, s+3,s);
                dtVmad(p0, s, delta, 0.5f);
                norm[0] = delta[2];
                norm[1] = 0;
                norm[2] = -delta[0];
                dtVnormalize(norm);
                dtVmad(p1, p0, norm, agentRadius*0.5f);

                // Skip backfacing segments.
                if (refs[j])
                {
                    unsigned int col = duRGBA(255,255,255,32);
                    dd.vertex(s[0],s[1]+agentClimb,s[2],col);
                    dd.vertex(s[3],s[4]+agentClimb,s[5],col);
                }
                else
                {
                    unsigned int col = duRGBA(192,32,16,192);
                    if (dtTriArea2D(m_spos, s, s+3) < 0.0f)
                        col = duRGBA(96,32,16,192);
                    
                    dd.vertex(p0[0],p0[1]+agentClimb,p0[2],col);
                    dd.vertex(p1[0],p1[1]+agentClimb,p1[2],col);

                    dd.vertex(s[0],s[1]+agentClimb,s[2],col);
                    dd.vertex(s[3],s[4]+agentClimb,s[5],col);
                }
            }
            dd.end();
            
            dd.depthMask(true);
        }
        
        if (m_sposSet)
        {
            dd.depthMask(false);
            duDebugDrawCircle(&dd, m_spos[0], m_spos[1]+agentHeight/2, m_spos[2], m_neighbourhoodRadius, duRGBA(64,16,0,220), 2.0f);
            dd.depthMask(true);
        }
    }
    
    if (m_nrandPoints > 0)
    {
        dd.begin(DU_DRAW_POINTS, 6.0f);
        for (int i = 0; i < m_nrandPoints; i++)
        {
            const float* p = &m_randPoints[i*3];
            dd.vertex(p[0],p[1]+0.1f,p[2], duRGBA(220,32,16,192));
        } 
        dd.end();
        
        if (m_randPointsInCircle && m_sposSet)
        {
            duDebugDrawCircle(&dd, m_spos[0], m_spos[1]+agentHeight/2, m_spos[2], m_randomRadius, duRGBA(64,16,0,220), 2.0f);
        }
    }
}

void NavMeshTesterTool::handleRenderOverlay(double* proj, double* model, int* view)
{
    GLdouble x, y, z;
    
    // Draw start and end point labels
    if (m_sposSet && gluProject((GLdouble)m_spos[0], (GLdouble)m_spos[1], (GLdouble)m_spos[2],
                                model, proj, view, &x, &y, &z))
    {
        imguiDrawText((int)x, (int)(y-25), IMGUI_ALIGN_CENTER, "Start", imguiRGBA(0,0,0,220));
    }
    if (m_eposSet && gluProject((GLdouble)m_epos[0], (GLdouble)m_epos[1], (GLdouble)m_epos[2],
                                model, proj, view, &x, &y, &z))
    {
        imguiDrawText((int)x, (int)(y-25), IMGUI_ALIGN_CENTER, "End", imguiRGBA(0,0,0,220));
    }
    
    // Tool help
    const int h = view[3];
    imguiDrawText(280, h-40, IMGUI_ALIGN_LEFT, "LMB+SHIFT: Set start location  LMB: Set end location", imguiRGBA(255,255,255,192));    
}

void NavMeshTesterTool::drawAgent(const float* pos, float r, float h, float c, const unsigned int col)
{
    DebugDrawGL dd;
    
    dd.depthMask(false);
    
    // Agent dimensions.    
    duDebugDrawCylinderWire(&dd, pos[0]-r, pos[1]+0.02f, pos[2]-r, pos[0]+r, pos[1]+h, pos[2]+r, col, 2.0f);

    duDebugDrawCircle(&dd, pos[0],pos[1]+c,pos[2],r,duRGBA(0,0,0,64),1.0f);

    unsigned int colb = duRGBA(0,0,0,196);
    dd.begin(DU_DRAW_LINES);
    dd.vertex(pos[0], pos[1]-c, pos[2], colb);
    dd.vertex(pos[0], pos[1]+c, pos[2], colb);
    dd.vertex(pos[0]-r/2, pos[1]+0.02f, pos[2], colb);
    dd.vertex(pos[0]+r/2, pos[1]+0.02f, pos[2], colb);
    dd.vertex(pos[0], pos[1]+0.02f, pos[2]-r/2, colb);
    dd.vertex(pos[0], pos[1]+0.02f, pos[2]+r/2, colb);
    dd.end();
    
    dd.depthMask(true);
}
